Toward(s)?

A friend of mine just rang me up with a urgent question, she did not know whether her use of 'towards' was correct or if 'toward' was more accurate. She told me she has been using 'towards' all her life, but lately have been hearing her lecturers use 'toward' instead. I realize that I have always been using 'towards' as well, and wanted to investigate the possible differences between the two forms. I ran a Google search on the difference between the terms and one search which showed a brief preview of a book, Painless Grammar by Rebecca Elliott Ph.D. She stated that the main difference between the 2 forms is 'that 'towards' is traditionally used in British English and 'toward' is more traditionally used in American English. The two words are both correct and can be used interchangeably.' Perhaps this is the reason why my friend and I were more familiar with 'towards' but her lecturers may have been educated in the US, and hence are 'primed' towards (:P) using 'toward'.
Having referred to a few online dictionaries, I can observe some patterns with regards to how subtle the affiliation between the British and American Englishes are, with 'towards' and 'toward', respectively.
The Oxford Advanced Learners Dictionary presented the lexical entry as such:

to•wards /twdz; NAmE trdz/ (also to•ward /twd; NAmE trd/ especially in NAmE) prep.
1 in the direction of sb/sth: They were heading towards the German border. She had her back towards me.
2 getting closer to achieving sth: This is a first step towards political union.
3 close or closer to a point in time: towards the end of April
4 in relation to sb/sth: He was warm and tender towards her. our attitude towards death
5 with the aim of obtaining sth, or helping sb to obtain sth: The money will go towards a new school building (= will help pay for it).

The OED was more neutral, in that it had separate entries for both 'towards' and 'toward', even going to the extent of pointing out subtle differences in usage like how 'toward' had an additional word class of being used as an adjective, on top of the common usages of preposition and adverb, which are shared with 'towards'.

The Merriam-Webster online dictionary (Am EL) in turn, presented its entry as such:

Main Entry: ¹to·ward

Pronunciation: \ˈtō-ərd, ˈtȯ(-ə)rd\

Function: adjective

Etymology: Middle English toward, from Old English tōweard facing, imminent, from tō, preposition, to + -weard -ward

Date: before 12th century

1also to·wards \ˈtō-ərdz, ˈtȯ(-ə)rdz\ [Middle English towardes, from Old English tōweardes, preposition, toward, from tōweard, adjective] a : coming soon : imminent b : happening at the moment : afoot
2 a obsolete : quick to learn : apt b : propitious, favoring

The fact that NUS' Vision, 'Towards a Global Knowledge Enterprise'uses 'towards' also shows how 'towards' is primed as the word form of choice by our community, which officially follows the BrEL version.